Single-shot 3D coherent diffractive imaging of core-shell nanoparticles with elemental specificity.

ABSTRACT: We report 3D coherent diffractive imaging (CDI) of Au/Pd core-shell nanoparticles with 6.1?nm spatial resolution with elemental specificity. We measured single-shot diffraction patterns of the nanoparticles using intense x-ray free electron laser pulses. By exploiting the curvature of the Ewald sphere and the symmetry of the nanoparticle, we reconstructed the 3D electron density of 34 core-shell structures from these diffraction patterns. To extract 3D structural information beyond the diffraction signal, we implemented a super-resolution technique by taking advantage of CDI's quantitative reconstruction capabilities. We used high-resolution model fitting to determine the Au core size and the Pd shell thickness to be 65.0?±?1.0?nm and 4.0?±?0.5?nm, respectively. We also identified the 3D elemental distribution inside the nanoparticles with an accuracy of 3%. To further examine the model fitting procedure, we simulated noisy diffraction patterns from a Au/Pd core-shell model and a solid Au model and confirmed the validity of the method. We anticipate this super-resolution CDI method can be generally used for quantitative 3D imaging of symmetrical nanostructures with elemental specificity.

SUBMITTER: Pryor A 

PROVIDER: S-EPMC5974371 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature